This article begins with a reflection on the place of the concept of "race" to comprehend the systems of social classification in Argentina in order to test if this is productive for the analysis of residential segregation in Puerto Madryn, a Patagonian city of recent growth. From the theoretical developments on the coloniality of power and racism in Latin America, rarely used in urban and anthropological analysis, the effects of hyper-visibility of migrants in the city are analyzed.